Razor blade cutter device and guard therefor



1952 D. K. HIGGINBOTHAM 3,015,887

RAZOR BLADE CUTTER DEVICE AND GUARD THEREFOR Filed Feb. 11, 1959 www United States Patent 3,015,887 RAZOR BLADE CUTTER DEVICE AND GUARD THEREFOR Daniel K. Higginbotham,P.0. Box 1957, Tulsa 1, Okla. Filed Feb. 11, 1959, Ser. No. 792,517 3 Claims. (Cl. 30162) The present invention relates to a razor blade cutting device, and more especially to a novel improved guard for a single edged razor blade providing an improved adjustable razor blade edge cutting device combination.

Safety razor blades have been found useful for many and varied purposes besides shaving, and a large number of razor blade holders and guard devices have been heretofore developed for use with such blades so that the cutting edge is protected and not exposed when the blade is not used, and so that the blade may be safely held for manipulating in cutting. (For example see United States Patents Nos. 1,038,896, 1,513,861, 1,745,535 and 2,599,439.) Devices of this kind heretofore available have various shortcomings and disadvantages which have precluded wide-spread acceptance. Some prior devices do not permit adjustment of the amount of razor blade exposed, and therefore do. not enable close self-regulation of the depth of cut by positioning of the guard. In some prior devices, part of the blade is exposed all of the time, and, although partially sheathed, the exposed blade section is a safety hazard. Most prior razor blade guards are relatively complicated, including multiple parts and/or complex shapes, and are therefore costly to make. Also in many such prior devices, the cutting edge of the blade is not positively prevented from engaging the guard during adjustment, and thereby becomes prematurely dull.

It is a primary object of the present invention to provide a new improved razor blade guard, and cutting device combination incorporating such guard, which overcomes the above-discussed and other shortcomings of devices of this type heretofore made available. More especially, it is an object of the present invention to provide a new improved razor blade safety guard which protects the user during manipulation of the blade, provides protection when the blade is not in use, and also is characterized by the following advantageous features:

(a) The guard is adjustable so that it is easy to regulate the length of the exposed cutting edge of the razor, thereby making it possible to readily control the depth of the cut through proper positioning of the guard.

(12) The design of the guard is such that it prevents the razor blade from cutting into the edge of a guide means like a plastic or wood straight edge, when used therewith. 1

(c) The razor blade guard is of utmost simplicity, with no rivets or screws or detachable parts, so that (1) it is very simple and economical to manufacture and assemble, and (2)- is easily detachable from the blade when desired. v. 7 p

(d) The guard may be easily reversed so that opposite ends of the blade maybe exposed and used, thereby doubling the useful life of the blade.

(e) The guard is designed to be made of such thin material that it affords the maximum in finger sensitiveness during use of the razor blade for close work like the cutting of seams in cloth.

The above and other objects of the present invention will be apparent from the following description thereof and appended claims, with reference to the accompanying drawings wherein:

FIGURE 1 is a perspective drawing of the new razor blade guard of the present invention;

FIGURE 2 is a perspective drawing of the improved cutting device of this invention, comprising a single edge ice razor blade with the guard of FIGURE 1 assembled thereon; 1 3

FIGURE 3 is a plan view of the razor cutting device shown in FIGURE 2, with the lower end of the razor exposed for cutting;

FIGURE 4 is a plan view of the razor cutting device of this invention, similar to FIGURE 3, but with the guard reversed on the blade so that the upper edge of the blade is exposed for cutting;

FIGURE 5 is a cross-section view of the blade and guard combination taken along line 5--5 in FIGURE 4; and

FIGURE 6 is a perspective view showing one of the various uses of the razor blade and guard combination of the present invention, namely ripping of a seam on two pieces of cloth.

Referring now to the drawings, especially FIGURES l-5, the present invention comprises a single edge razor blade generally indicated at 10, and the novel guard of the present invention generally indicated at 12. The blade 10 has the usual stiff channel back guard 14, and razor edge 16, and is provided with a pair of narrow elongated slots 18, each of which is about A in length and runs parallel with the cutting edge 16 of the blade. The slots 18 are of a suitable width, and in a typical embodiment would be approximately V The guard 12 is formed of thin spring tempered material, such as 0.005'. brass, is of substantially the same length as the blade knife edge 16, and is folded to provide one relatively narrow side 20 and one wider side 22 (see especially FIGURES 1 and 5). The wider side 22 is provided with two small indentations 24, 'which form detents extending towards the narrow side 20. The blade 10 is inserted between the two guard sides 29 and 22, and the detents 24 are received in the slots 18 of blade 10, in a manner which is apparent from the drawings. The guard 12 is designed so as to expose one cutting end portion at a time of the blade edge 16, to a length of approximately 4". The detents 24 ride in slots 18 so that the guard 12 can be slid back and forward on the blade 16 exposing a variable cutting sec-. tion 16 FIGURE 2 and the detents 24 are spaced apartso that when the cutting edge is not in use the guard 12' may be returned to a position that completely sheathes the blade cutting edge 16.

Referring especially to FIGURE 4, each of the de-' tents 24 is positioned from the adjacent edge of the guard 12 substantially the same distance as the point a at the upper end of each slot 18 is positioned from the adjacent end of the razor blade'll). Also the distance between the lower end b of each slot 18 is equal to the distance between the upper end points a on slots 18. The detents 24 are spaced from each other substantially the same dis-' tance as the spacing between slot ends b--b, and/or slot ends aa.

With the above described construction, only one end of the blade edge is exposed for cutting, the other be: ing held in reserve and available for use simply by reversing the guard on thebla'de; To remove tlie'guard, for the purpose of changing the exposed end of the blade, or for the purpose of inserting a new blade, it is only necessary to lift the wider guard side 22 slightly away from the blade and then slide the guard 12 off the blade. This can be done easily by inserting the thumb nail, a pencil point or the like, through the aperture 28 to displace guard side 22. The removed guard is simply turned end for end, as will be apparent from a comparison of FIGURES 3 and 4, and blade 10 inserted between sides 20 and 22 of the guard with the detents 24 dropping into place in the slots 18 on the other side of the blade (compare FIGURES 3 and 4). It will be apparent that the removal and reassembly of the novel improved guard of the present invention is a very simple matter.

Besides providing a means for adjusting the exposed blade cutting edges 16 to any desired length by displacement of the guard 12, the above-described arrangement of slots and indentations (18, 24) constitutes an improved safety feature, because, when thus atfixed to the blade, the guard 12 will not become easily detached from the blade excepting by a prying up action as above described.

Furthermore, the blade slots and guard indentations arrangement provides another distinct and advantageous feature. The distance between the indentations 24 and the inside fold 30 of the guard 12 is slightly greater than the distance between the longitudinal axis of the slots 18 and the outermost portion of the cutting edge 16 of the blade 10, so that the blade cutting edge 16 is positively prevented from coming into contact with the guard 12 at any time. As a result, the back and forth movement of the guard 12 does not dull the blade cutting edge 16, which would be the case if contact between the blade edge and the guard were thus not controlled and prevented.

It will be noted that the major portion of the blade cutting edge 16 is covered by the guard 12, thus protecting the user during manipulation of the cutter device of this invention, while the depth of cut desired can be regulated by the amount of the blade edge 16 left outside of the guard 12. The razor cutting device combination of this invention is thereby very safe to use, but has considerable flexibility, and is especially useful where it is important to regulate the depth of cut on the work piece, or protect a working guide means such as a straight edge.

Referring especially to FIGURE 6, there is shown a representative use for the razor blade cutting device combination of the present invention, namely the ripping of a seam 31. The extent of the blade edge 16 exposed, and the angle of the blade with respect to the work, can be readily controlled to govern the depth of cut, so that there is little or no danger of cutting the cloth 32 while the seam is quickly severed.

Another application where the guarded razor blade cutting device of the present invention'is particularly useful is in cutting of material using a plastic or wood straight edge as a guide, since the guard permits exposure of the desired length of cutting edge while keeping the remainder of the blade edge sheathed. This prevents the razor from cutting the straight edge or like guide means, a well-known undesired experience to draftsmen and artists. Still another use made safer and more practical by the guarded razor combination of this invention, is the convenient removal of back and cover material on pressuresensitive tapes or like items. The paper backing on such pressure-sensitive tapes, labels, or the like can be s'lit, with the depth of cut made by the exposed razor blade edge 16 being controlled by position of the guard 12 and elevation of the blade so that only the backing paper is cut. Thereafter, the slit portion on the backing paper may be grabbed more readily so that the backing paper can be removed quite easily. It is obvious that there are many other uses for the present invention; e.g., in the home'for opening cardboard containers, especially with cellophane wrappers, by draftsmen or artists to make erasures, etc.

It will be apparent from the foregoing description that the present invention provides a novel improved simplified razor blade guard, and a novel improved simplified razor blade cutting combination incorporating such guard, which (1) achieves the desirable objects and advantages in safety, new uses, improved results, and (2) solves shortcomings and disadvantageous aspects of the prior devices of this kind, as discussed in the introduction of this application.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. A cutting device comprising: a single edged razor blade having a non-cutting back portion, sides, a cutting edge, and a plurality of elongated narrow slots with longitudinal sides extending parallel to said cutting edge of the blade; and a channel-shaped guard of sheet material on said blade, said guard having two sides spaced from each other a distance slightly less than the thickness of the razor blade when the guard is not assembled thereon, with said cutting edge received therebetween, the length of said guard sides being substantially the same as the length of the blade, said guard having a plurality of detents thereon extending from one side of the guard towards the other side thereof, with each of said detents received in one of said elongated slots in the razor blade, so that the guard is movable with respect to the blade whereby the length of the blade edge exposed can be adjusted, the distance from each of said detents to the edge of the guard joining its two sides being slightly greater than the distance between the respective slots receiving the detents and the cutting edge of the blade, whereby the blade cutting edge is prevented from contacting the guard when it is moved to adjust the length of the blade cutting edge exposed.

2. A cutting device as defined in claim 1, wherein one side of said channel-shaped guard is wider than the other side thereof, and said detents are on said wider side, disposed beyond the free edge of the other narrower side.

3. A cutting device as defined in claim 2, wherein said razor blade has an aperture that extends therethrough beyond the free end of said other narrower side of the channel guard, and is at least in part overlapped by said wider side of the channel-shaped guard.

References Cited the file of this patent UNITED STATES PATENTS 

